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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Genetic considerations in cloning western hemlock /

Foster, George Samuel, January 1983 (has links)
Thesis (Ph. D.)--Oregon State University, 1984. / Typescript (photocopy). Includes bibliographical references (leaves 96-99). Also available on the World Wide Web.
2

The influence of pre-harvest killing of western hemlock on subsequent stump invasion by Fomes annosus /

Laird, Peter Paul. January 1971 (has links)
Thesis (Ph. D.)--Oregon State University, 1971. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
3

Provenance variation in Western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings /

Kuser, John E. January 1980 (has links)
Thesis (Ph. D.)--Oregon State University, 1980. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
4

Growth and moisture relations of western hemlock seedlings as affected by root or shoot disturbance /

Morris, John W. January 1978 (has links)
Thesis (M.S.)--Oregon State University, 1979. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
5

Patterns of growth and seasonal changes in the concentrations of abscisic acid and indoleacetic acid in roots of western hemlock /

Brown, Charles Joseph. January 1976 (has links)
Thesis (M.S.)--Oregon State University, 1977. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
6

The physiology of dormancy of western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings /

Nelson, Eric Alan. January 1978 (has links)
Thesis (Ph. D.)--Oregon State University, 1978. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
7

Crown structure and stem form development in young stands of western hemlock /

Kershaw, John A., January 1993 (has links)
Thesis (Ph. D.)--University of Washington, 1993. / Vita. Includes bibliographical references (leaves [208]-235).
8

Structural development of late successional forests in the central Oregon Coast Range : abundance, dispersal, and growth of western hemlock (Tsuga heterophylla) regeneration /

Schrader, Barbara A. January 1998 (has links)
Thesis (Ph. D.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references (leaves 154-160). Also available on the World Wide Web.
9

Edaphic aspects of an ecological classification of the Interior Western Hemlock dry Subzone forests of British Columbia.

Smith, Richard Barrie January 1963 (has links)
Edaphic information from 168 plots in the Interior Western Hemlock (Tsuga heterophylla (Raf.) Sarg.) Dry Subzone of southeastern British Columbia was used to describe soils and to elucidate some relationships concerning soils and soil-forming factors, and soil and vegetation. Characteristics described from soil pits in each plot included thickness, depth and boundary of horizons, soil texture, structure, consistence and mottling. Color and pH were determined on 1,100 soil samples. In addition, 450 samples from 70 selected profiles were chosen for analysis of exchangeable calcium, magnesium, potassium, and sodium, adsorbed phosphate, total nitrogen, cation exchange capacity, organic carbon and calcium carbonate equivalence. Rock samples were collected and identified to aid in the determination of the nature of the parent material. Seepage water from 40 plots was analysed for calcium, magnesium and potassium content. Observations on physiography, relief, exposure, elevation, slope, drainage and erosion were recorded for each plot. Ninety Colman Fiberglas units were established in 15 plots to determine soil moisture and temperature trends. An estimation of biological activity in 15 plots was made using the loss in breaking strength of cotton duck as the criterion. Nineteen soil monoliths were prepared and over 70 color photographs taken for illustrative and comparative purposes. Soil classification generally followed current Canadian practices to the sub-group level. Certain profiles were found difficult to classify at the sub-group level. These, however, were placed in sub-groups resembling them most closely. Further subdivisions, based mainly on moisture and surface soil conditions and reflecting productivity, were formed by prefixing terms to some of the sub-group names (e.g. Dry Orthic Brown Wooded, I Normal Minimal Podzol, Moist Orthic Podzol). Of the 29 soils distinguished, the Normal Orthic Podzol, Ortstein Podzol, and I Normal Minimal Podzol were considered to represent the zonal soils of the sub-zone. These soils were oligotrophic (base saturations of B generally less than 20 per cent), and were characterized by a felty mor humus, conspicuous Ae, and a bright yellowish brown B, all of which reflected the dominant soil-forming process of the area which is podzolization. Departures from the zonal pattern, however, were numerous. Dry soils tended to have a thin F-H layer and a thin, discontinuous or absent Ae, Seepage influences ranged from an increase of exchangeable bases and humus friability in Moist Orthic and Minimal Podzols, to a build-up (over 30 cm) of organic material in Shallow and Deep Mucks. Soils such as the Dry and Normal Orthic Brown Woodeds, characterized by the absence of Ae and a base saturation generally over 50 per cent, were associated with parent materials rich in calcium especially in dry topoclimates. Where both calcareous parent material and seepage combined, soils most unlike the zonal were produced (e.g. Calcareous Duff Mull Regosol). Podzolization was less effective on steep slopes especially in warm topoclimatic situations. It reached its maximum (Ortstein Podzol) on neutral or slightly concave relief of gentle to moderate inclination, or on coarse, old, excessively drained alluvium or outwash. Brunisolic soils seldom occurred on alluvium or outwash, while strongly podzolized soils were rare in areas underlain by bedrock of the Lardeau series, Sinemurian beds and Rossland formation, or the eastern portion of the Slocan group. Seepage from pits in the vicinity of Lardeau and Slocan bedrock was higher in calcium and magnesium than seepage from other locations. Statistically significant differences occurred between sites in estimated biological activity. Moist and extremely dry sites showed high activity compared to intermediate, well-drained sites with more strongly podzolized soils. A classification of soils by moisture supply (hygrotope) and chemical characteristics (trophotope) was suggested. Associations and ecosytem types determined by an independent investigator from phytocoenotic and general environmental data corresponded fairly closely to the nature of the soil. The correspondence was, however, less apparent in moist than in dry and wet sites. / Science, Faculty of / Botany, Department of / Graduate
10

Forest types of the coastal western hemlock zone

Orlóci, László January 1961 (has links)
This thesis contributes analytical and synthetical data on the forest phytocoenoses and proposes a classification. Detailed floristical and environmental descriptions are given, also consideration of succession and life-form distribution. The following ecosystem classification is proposed: I. Dry edaphic and mesic zonal forest types of the dry subzone. 1) Pseudotsugetum menziesii a) subassoc. tsugetosum heterophyllae or the orthic Gaultheria forest type b) subassoc. legosolicum or the legosolic Gaultheria forest type c) subassoc. mahonietosum or the Gaultheria - Mahonia forest type 2) Tsugetum heterophyllae Subassoc. plagiothecietosum undulati a) var. muscosum or the orthic Plagiothecium forest type b) var. mahoniosum or the Plagiothecium - Mahonia forest type II. Dry edaphic and mesic zonal forest types of the wet subzone 3) Tsugeto – Gaultherietum a) subassoc. typicum or the orthic Vaccinium alaskaense - Gaultheria forest type b) subassoc, legosolicum or the legosolic Vaccinium alaskaense - Gaultheria forest type 4) Abieteto - Tsugetum heterophyllae a) vara clintoniosum or the Vaccinium alaskaense - Plagiothecium - Clintonia forest type b) var. acerosum circinati or the Vaccinium alaskaense - Plagiothecium - Acer circinatum forest type III. Seepage forest types 5) Thujeto - Polystichetum or the Polystichum forest type 6) Thujeto – Blechnetum a) subassoc. typicum or the orthic Blechnum forest type b) subassoc. gleysolicum or the gleysolic Blechnum forest c) subassoc. turfosum or the peaty Blechnum forest type d) subassoc. rubetosum vitifolii or the Blechnum - Rubus vitifolius forest type 7) Abieteto - Oplopanacetum or the Oplopanax - Adiantum forest type 8) Piceeto - Lysichitetum or the Vaccinium alaskaense - Lysichitum forest type IV. Moor forest types 9) Pineto - Ledetum or the Ledum forest type 10) Thujeto - Coptetum or the Lysichitum - Coptis forest type V. Flood plain forest types 11) Piceeto - Symphoricarpetum or the Symphoricarpos - Disporum forest type 12) Piceeto – Oplopanacetum a) var. populosum trichocarpae or the Ribes braeteosum - Oplopanax - Populus forest type b) var. abietosum amabilis or the Ribes bracteosum - Oplopanax - Abies amabilis forest type 13) Populeto - Loniceretum or the Lonicera - Rubus spectabilis forest type 14) Alneto - Ribisetum bracteosi or the Ribes bracteosum - Lysichitum forest type 15) Saliceto - Oenanthetum or the Lysichitum - Oenanthe forest type. The floristic structure of the phytocoenoses was studied, described and correlated with factors of the environment. Variations in the floristic and ecotopic characteristics of the units support this classification. These characteristics were used in the key proposed for identification of the forest types. Forest types as basic ecosystem units are offered for practical use. They are uniform in composition and, therefore, potentionally they require different treatments in forest management. / Science, Faculty of / Botany, Department of / Graduate

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